Thermometer installation.



L. S. CHADWICK.

THERMOMETER INSTALLATION.

APPLICATION FILED numal. 19:4.

Patnted Aug. 6, 1918.

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ATENT rum LEE S. CHADWICK, OF EAST CLEVELAND, OHIO, ASSIGNOR TO THE CLEVELAND METAL PRODUCTS COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

THERMOMETER INSTALLATION.

Specification of Letters Patent.

Patented Aug. 6, 1918.

Application filed August 31, 1914. Serial No. 859,338.

7 T 0 all whom it may concern.-

Be it known that I, LEE S. CHADWICK, a citizen of the United States, residing at East Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Thermometer Installations, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings.

This invention has reference to a novel manner of incorporating or installing thermometers within heat insulating members, such as the doors or walls of ovens and other like structures.

The use of thermometers in connection with ovens for determining their internal temperatures without having to open the oven door, has been found a great convenience and materially facilitates the cooking operation or process by removing the need of having to frequently open the oven door for such purpose. However, in all constructions with which I am familiar, and which have as their purpose the attainment of the above object, there is a direct connection of heat conducting material between the outer and inner metallic plates whereof the shell of the member embodying the thermometer is formed, and this results in the loss of a considerable amount of heat, and, consequently. a decided decrease in the efficiency of the oven.

It is the primary object of my invention, therefore, to provide a member of the aforesaid character within which is embodied a thermometer that may be readily acted upon or affected by the temperature upon one side of said member and easily observed from the opposite side thereof, the nature of its construction preventing leakage or passage of heat from one to the other side of said member.

The above object stated in more limited terms, is the provision of a member comprising an inner and an outer metallic plate that are separated by a layer of non-heat conducting or heat insulating material. the same having incorporated within it a thermometer that is subjected to the temperature upon one side of the member and protected from the temperature on the other side thereof; the presence of the thermometer requiring no connections of heat conducting material between the inner and outer metallic plates of the member.

A further object of the invention is to provide a simple, economical, thoroughly practical and extremely efficient construction of such members.

Inasmuch as my invention is especially suitable for use in connection with ovens, and particularly the doors or closures thereof, I have shown it in such connection in the accompanying drawing wherein Figure 1 is a section through an oven closure and an adjacent portion of the oven wall, a thermometer being incorporated within the closure in accordance with my invention; Fig. 2 is a front elevation of a portion of the closure in the vicinity of the thermometer; and Fig. 3 is a rear view of the same part of the closure.

To the forward edge of the oven wall 1 is hinged at 2, the door or closure 3. The

wall 1 is shown as consisting'of a metallic' shell that is filled with non-heat conducting material.

The member A in which the thermometer is mounted (the door of the oven in this instance) comprises an inner plate 5 and an outer plate (3 between which is a layer or filling of non-heat conducting or insulating material 7, such as asbestos. The inner and outer plates have openings 8 and 9, respectively, that are, or may be, surrounded by flanges 10 and 11. It will be seen that the opening 9 is of lesser diameter than the opening 8, and that there is a cavity 12, through the layer of insulating material 7 which is in axial alinement with the openings 8 and 9. WVithin the outer end of the cavity 12, and located adjacent the plate 6, is an annular member- 15 which comprises two radially spaced concentric walls that are con- .nected by a web 16. A finishing ring 17,

fits within the inner wall of the annular member 15 and may be secured thereto in any approved manner, the ring having its outer end turned over to conceal the flange 11. A disk 18 of transparent material, such as a crystal of glass, may be placed, through the opening 8, into the cavity 12, from the inside of the member A, against the inner edge of the finishing ring 17, and this disk is held in place by a sleeve 20 of non-heat conducting material which is pressed into the cavity 12, also from the inner side of the member A. The sleeve therefore, is, in effect, a liner for the cavity, and when the cavity is referred to hereinafter it is intended to mean the space withinthe sleeve, unless restricted, by the language, to the cavity proper.

The thermometer, which is shown generally at 21, is contained within the cavity, or to be more exact, within the sleeve 20, and has connection with a plate 22, through the prongs 23 which project from the rear end of the thermometer casing, through slots 24 that are formed in the plate 22. The plate 22 is secured to the member A- by means of screws 25 which pass through perforated ears 26 of the plate 22 and through the adjacent portion of the inner plate 5 of said member and are threaded into nuts or blocks 27 that are secured to the inner surface of theplate 5.'

It will be observed that the depth of the thermometer 21 (in the embodiment shown herein) is some less than that of the cavity which it occupies, whereby an air space is provided between the front of the thermometer and the disk 18; and furthermore that there is no connection between the inner plate 5 and the outer plate 6, in the vicinity of the cavity, except through non-heat conducting material, thereby elin'iinating the 1. The combination of a member com-' prising an inner and an outer plate that are separated by a layer of'non-heat conducting material, one of said plates having an opening and the layer having a cavity that are in axial alinement, the opening being of lesser diameter than the cavity, an annular member within the cavity adjacent the open ing, a ring within the opening and having an extension which projects into the annular member, a disk of transparent material within the annular member and resting against the end of the said extension, a sleeve of non-heat conducting material in the cavity and one end of which engages the periphery of the transparent disk, and a thermometer within the sleeve the dial whereof is spaced from the transparent disk.

2. The combination of a member comprising an inner and an outer plate that are separated by a layer of non-heat conducting material, the inner plate, the layer, and the outer plate having openings that decrease in diameter in the order named, afinishing ring within the opening of the outer plate and having a portion which is flared outwardly over the adjacent portion of the front plate and having also an extension which projects into the opening of the layer, an annular member within the last mentioned opening adjacent the front plate wherewith the finishing ring is connected, a disk of transparent material within the annular member and bearing against the extension of the aforesaid ring, a sleeve of non-heat conducting material within the opening of the layer one end whereof bears against the periphery of the disk, a thermometer within the sleeve and'having its dial spaced from the disk, and means whereby the thermometer is connected to the inner plate of the member.

In testimony whereof, I hereunto affix my signature in the presence of two witnesses.

' LEE s. CHADWICK.

\Vitnesses:

W. E. SHEPPARD, F. J TROTIER. 

